The paper presents a method for determining sets of Pareto optimal solutions (compromise sets) - parameter values of PSS3B
system stabilizers working in a multi-machine power system - when optimising different multidimensional criteria. These criteria are
determined for concrete disturbances when taking into account transient waveforms of the instantaneous power, angular speed and terminal
voltage of generators in one, chosen generating unit or in all units of the system analysed. The application of multi-criteria methods allows
taking into account the optimisation process of power system stabilizer (PSS) parameters, many sometimes contradictory requirements
(criteria) without losing ability to reach the optimal solution. A choice of the compromise solution can be made by assuming the values
of the weighting coefficients associated with particular components of the vector criterion and determining the equivalent, global criterion.
A change of the values of those weighting coefficients in the equivalent criterion does not require, in the case of the Pareto optimization,
carrying out repeated calculations.